Add path.joinAll.

pkg/path/lib/path.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// A comprehensive, cross-platform path manipulation library.
 library path;
 
 import 'dart:io' as io;
 
 /// An internal builder for the current OS so we can provide a straight
@@ skipping 94 matching lines @@
 ///
 ///     path.join('path/', 'to', 'foo'); // -> 'path/to/foo
 ///
 /// If a part is an absolute path, then anything before that will be ignored:
 ///
 ///     path.join('path', '/to', 'foo'); // -> '/to/foo'
 String join(String part1, [String part2, String part3, String part4,
             String part5, String part6, String part7, String part8]) =>
   _builder.join(part1, part2, part3, part4, part5, part6, part7, part8);
 
+/// Joins the given path parts into a single path using the current platform's
+/// [separator]. Example:
+///
+///     path.joinAll(['path', 'to', 'foo']); // -> 'path/to/foo'
+///
+/// If any part ends in a path separator, then a redundant separator will not
+/// be added:
+///
+///     path.joinAll(['path/', 'to', 'foo']); // -> 'path/to/foo
+///
+/// If a part is an absolute path, then anything before that will be ignored:
+///
+///     path.joinAll(['path', '/to', 'foo']); // -> '/to/foo'
+///
+/// For a fixed number of parts, [join] is usually terser.
+String joinAll(Iterable<String> parts) => _builder.joinAll(parts);
+
 // TODO(nweiz): add a UNC example for Windows once issue 7323 is fixed.
 /// Splits [path] into its components using the current platform's [separator].
 ///
 ///     path.split('path/to/foo'); // -> ['path', 'to', 'foo']
 ///
 /// The path will *not* be normalized before splitting.
 ///
 ///     path.split('path/../foo'); // -> ['path', '..', 'foo']
 ///
 /// If [path] is absolute, the root directory will be the first element in the
@@ skipping 189 matching lines @@
   /// be added:
   ///
   ///     builder.join('path/', 'to', 'foo'); // -> 'path/to/foo
   ///
   /// If a part is an absolute path, then anything before that will be ignored:
   ///
   ///     builder.join('path', '/to', 'foo'); // -> '/to/foo'
   ///
   String join(String part1, [String part2, String part3, String part4,
               String part5, String part6, String part7, String part8]) {
+    var parts = [part1, part2, part3, part4, part5, part6, part7, part8];
+    _validateArgList("join", parts);
+    return joinAll(parts.where((part) => part != null));
+  }
+
+  /// Joins the given path parts into a single path. Example:
+  ///
+  ///     builder.joinAll(['path', 'to', 'foo']); // -> 'path/to/foo'
+  ///
+  /// If any part ends in a path separator, then a redundant separator will not
+  /// be added:
+  ///
+  ///     builder.joinAll(['path/', 'to', 'foo']); // -> 'path/to/foo
+  ///
+  /// If a part is an absolute path, then anything before that will be ignored:
+  ///
+  ///     builder.joinAll(['path', '/to', 'foo']); // -> '/to/foo'
+  ///
+  /// For a fixed number of parts, [join] is usually terser.
+  String joinAll(Iterable<String> parts) {
     var buffer = new StringBuffer();
     var needsSeparator = false;
 
-    var parts = [part1, part2, part3, part4, part5, part6, part7, part8];
-    _validateArgList("join", parts);
-
     for (var part in parts) {
-      if (part == null) continue;
-
       if (this.isAbsolute(part)) {
         // An absolute path discards everything before it.
         buffer.clear();
         buffer.add(part);
       } else {
         if (part.length > 0 && part[0].contains(style.separatorPattern)) {
           // The part starts with a separator, so we don't need to add one.
         } else if (needsSeparator) {
           buffer.add(separator);
         }
@@ skipping 349 matching lines @@
     // If there is no dot, or it's the first character, like '.bashrc', it
     // doesn't count.
     if (lastDot <= 0) return [file, ''];
 
     return [file.substring(0, lastDot), file.substring(lastDot)];
   }
 
   _ParsedPath clone() => new _ParsedPath(
       style, root, new List.from(parts), new List.from(separators));
 }